The latest 13F season has arrived, when many money managers issue required reports on their holdings. It can be worthwhile to pay attention, as you might get an investment idea or two by seeing what some major investors have been buying and selling.

For example, consider Bridgewater Associates, one of the world's largest hedge fund companies. According to its recently released 13F statement, Bridgewater has boosted its positions in Eldorado Gold (EGO -4.85%) and Health Care REIT (WELL 0.32%), while initiating a position in Maxim Integrated Products (MXIM) in a big way.

You don't buy Eldorado Gold for its dividend, which recently yielded 0.3% -- and probably not for a cheap valuation, either, with its forward price-to-earnings ratio near 24. But you might buy it if you see gold prices surging in the coming years and have confidence in its operations. Eldorado's latest quarterly report featured revenue and earnings below expectations, in part due to impairment charges tied to two mines in China. Gold production rose 10%, though. Eldorado expects a 6% production increase in 2014, and the low-cost producer plans to continue reining in costs.

Health Care REIT is focused on buying senior-living facilities, as well as hospitals and other medical properties, which it then leases back to occupants. It offers a fat 5.4% dividend yield, though it has been paying out more than it brings in via earnings lately, which is not sustainable over the long run. Still, the company is performing well, has been growing aggressively via acquisitions, and is poised to benefit from aging baby boomers. Its fourth quarter featured funds from operations, or FFO, growing by 16% over year-ago levels and full-year FFO rising 8%. The quarter also featured nearly $278 million spent on 12 property acquisitions and total revenue surging some 59%.

Maxim Integrated Products, which specializes in linear and mixed-signal integrated circuits, is a tech company offering a solid dividend yield of 3.5%. In its last quarter, Maxim posted earnings that beat analyst expectations and revenue that disappointed those observers. Still, bulls like Maxim's innovation and diversification and are optimistic about its acquisition of Volterra Semiconductor. With a forward P/E near 16 -- about half its five-year average of 33.5 -- Maxim Integrated Products is appealingly priced. In late January, analysts at several research firms upgraded the stock, setting a target price of $35. A Barclays analyst cited the company's expansion in the mobile arena (via sensors and motion-control technology for smartphones, tablets, and more), along with its presence in the Samsung GS5.